The blending of textile fibers for large lots historically has presented difficulties and has been very costly to attain. In certain textile goods, particularly carpets, precise uniformity throughout a lot is necessary to prevent "streaking", namely noticable change in color or texture of a carpet or other textile product which is not a part of the desired product variation. Blending in other textile operations, in large lots, also is desirable. Over the years, several schemes of blending large lots have been used. However, all of them are labor intensive or very costly both in terms of equipment and building space.
One system previously employed involves assemblying a small percentage at a time of bales of fiber to be blended and placing segments of these bales in a number of side by side opening machines which feed a common baling press. Up to 50 bales may be represented in one bale at the baling press. A succession of bales thus pre-blended are placed in a staging room sequentially in rows. After this first pre-blending the bales are then removed from these rows crossways from the way they were placed in the staging area. The removal of the rows of pre-blended bales from the staging area now will contain in each row fibers from the very first bales of the lot to the very last bales of the lot. These crossway rows of bales are then rerun through the same blending equipment and baling presses as the first pass. With these two passes a sufficiently uniform blend of fibers usually is obtained to eliminate obvious streaking.
Another prior art method of blending textile fibers for carpet yarns and the like is to employ huge blending chambers. These chambers may be approximately 100 feet long by 14 or 15 feet wide and 15 feet high. The fibers are fed from bales in succession to an opening machine or machines and an oscillating distributing device layers the fibers up and down the 100 foot length of the blending chamber until the chamber is filled. A typical full chamber will contain up to 50 bales. When the chamber or room is filled an unloading device removes the fibers from the chamber, starting at one end of the 100 foot length. The unloading device removes fibers simultaneously throughout the full height and width of the layered fibers; thus, a considerable amount of blending is accomplished. However, even if the lot size to be blended is no more than 50 bales representing the capacity of the chamber, a second stage of layering into a large blending chamber of the same type normally is used to insure the desired, proper blending. In many instances, however, the lot size desired to be blended exceeds the volumetric capacity of even these huge chambers; therefore, a succession of lots of fibers to be blended must be passed through the chambers. In order to assure that these successive lots are uniform from one to the other, the fibers must be baled after the first pass and collected in rows as with the first system above described. The fibers then must be rerun through the same equipment taking the bales away from the bale staging area in rows crosswise to the rows of bales as they were placed in the staging area.
In the blending of fibers for textile products other than carpet yarns, two systems currently are used. One system employs an overhead traveling grab mounted on a bridge in such fashion that the grab may travel the length of the bridge. The bridge is mounted on stationary tracks at either end so that it may travel from end to end of the tracks. In this way the grab may be positioned at any point over an area on which rows of bales are placed. The grab is moved downwardly until it contacts the surface of a bale whereupon the grab fingers close, grasping an indefinite amount of fibers. In practical operation the amount the grab picks up varies from nothing to perhaps 30 pounds. Once the grab has seized some of the fibers it is raised and travels along the bridge, the bridge in turn traveling along the tracks to a point where the grab releases its fibers into the succeeding opening and blending machine. While this system in some respects is satisfactory, it is limited in capacity since most all of its operating time is taken in travel to and from the respective bales to the succeeding blending machine. Since the grab involves fingers, this apparatus is very erratic in the amount of fiber removed and oftentimes drops some of the fibers on the way to the blending machine.
Another and perhaps the latest device being used today for general textile fiber blending is an apparatus that employs a floor-mounted traveling column. The travel of the column is limited to an oscillating motion up and down a straight path. Cantilevered to one side of the column, at 90 degrees from the direction of tower travel, is an arm supporting a mechanical device which can remove relatively uniform amounts of fiber from a single row of bales laid down under the cantilevered arm and running parallel to the travel of the tower. Also associated with this arm and tower and mechanical fiber removal device is a conduit through which air is drawn, thus to entrain the fiber removed from the successive bales. The conduit in the traveling tower is slidably connected to a stationary conduit which runs the length of the travel of the tower and has an open top. The open top of such conduit is covered by a sliding belt which passes over pulleys or wheels at either end of the conduit, the belt also running underneath the conduit. Thus, such belt makes a continuous loop over the two pulleys but is tied to the discharge end of the conduit carried by the tower leaving an opening between the moving and stationary conduits. The airborne stream of fibers passing through the conduit in the arm and tower are thus drawn into the stationary conduit. The belt just described makes an air-tight seal over the open top of the stationary conduit at all points except the point at which the conduit in the tower discharges the air and fiber into the stationary conduit. The stationary conduit has a discharge opening at one end from which the air and fiber pass to the succeeding blending machinery where the fibers are separated from the air stream. It will thus be seen that the apparatus just described has the advantage of continuous operation in which the fibers may be removed from the bale while the fiber is being conveyed from the bales to the succeeding blending machinery. The rate of fiber removal in this machine is considerably increased over the grab method described earlier. However, this last described method is limited to a single row or at most two rows of bales, at most 60 or 80 bales. Therefore this machine is not suitable for blending large lots of bales.
The foregoing describes the prior art as it is known to us. As will appear hereinafter our invention has for its general objects to overcoxe the several disadvantages of the above mentioned prior art apparatus.